Process and apparatus for the compressive shrinking of fabrics



Oct. 3, 1961 B. E. SCREETON ETAL 3,002,251

PROCESS AND APPARATUS FOR THE COMPRESSIVE SHRINKING OF FABRICS Filed March 7, 1958 Inventors Attorneys Uni e S es This invention relates to the shrinking of textile fabrics and to apparatus for use therein.

It is well known that textile fabrics can be compressively shrunk by compressive forces applied lengthwise thereto along the path of travel of the fabric. Usually the fabric is pressed between the contractible surface of a belt and a heated metal roller while the contractible surface contracts, the fabric entering a nip between the heated roller and the surface of the belt at a point where the belt is passing around another roller. The heated metal roller may be replaced by a heatedplate. In another form of machine the fabric is nipped between two rollers and fed by them through a very narrow passage from which it is forced to emerge at a slower speed and in which it is prevented from buckling as a whole so that it is forced to shrink lengthwise.

To be shrunk in the above fashions a cellulosic fabric, for example, must be moist and hot, because then it is in what is commonly regarded as a plastic state. Other fabrics may require only heat. The heat is applied to the fabric by the heated metal roller or plate or one or both walls of the passage.

The face of the fabric which comes into contact with the heated surface becomes glazed as it slips over that surface. This has long been recognized as a disadvantage of compressive shrinking.

It is an object of this invention to avoid, or at least to reduce, this glazing.

It is another object of this invention to provide improved compressive shrinking apparatus having a reduced tendency to cause glazing of a fabric during shrinking.

The reduction in the glazing is effected, according to the invention, by engraving the heated surface, or each heated surface, with schreiner lines extending in the direction of travel of the fabric.

Schreiner lines are very shallow grooves very close to one another, and they are commonly used in calendering machines. When such lines are engraved on the heated surface of a compressive shrinking machine, corresponding lines appear in the cloth in the direction of the warp. They are almost too fine to see with the naked eye but they break up the glaze and do not affect shrinking.

It is known to engrave schreiner lines parallel to the axis of the heated roller of a compressive shrinking machine, but this is ineffective in eliminating glaze. The reason is that if such transverse schreiner lines are reproduced on the fabric they are immediately largely eliminated again by the frictional slipping of the fabric on the heated roller. Moreover, transverse schreiner lines quickly wear smooth, and before they are worn smooth they actually reduce the amount of shrinkage by reducing the slip of the fabric on the heated surface.

Schreiner lines extending in the direction of travel of the fabric on the other hand both reduce the glaze substantially and have a substantial life.

The invention is particularly useful in processes in which the fabric is pressed between the contractible surface of a belt and a heated roller. In order to reduce glaze as much as possible, the whole surface of the roller in contact with t e fabric should be engraved with atent schreiner lines running around the circumference of the roller in parallel planes all perpendicular to the axis of the roller.

In the accompanying drawings, FIGURE 1 shows such a compressive shrinking machine diagrammatically;

FIGURE 2 shows the surface of the heated roller del veloped;

FIGURE 3 resembles FIGURE 2, but shows a pattern of engraving; and

FIGURE 4 indicates another engraving pattern.

I In FIGURE 1, the fabric is shown at 1 and is shrunk in a shrinking apparatus in which it is compressed between a roller 2 which is heated during the shrinking process and an endless contractible belt 3 that travels around two rollers 4 and 5, the heated roller pressing against the belt to produce a concave curvature in it. After leaving this apparatus the fabric travels to a Palmer dryer with a drum 6.

FIGUREZ shows a development of the surface of the roller 2 with parallel schreiner lines 7 running around the, circumference. The direction of travel of the fabric over the surface is indicated by an arrow.

It is not necessary to use such parallel lines over the wholeheated surface, and indeed the schreiner engraving may be in the form of a pattern so as to produce a patterned effect on the fabric. This pattern may be formed as shown in FIGURE 3 by engraving part of the heated surface with lines 8 parallel to the direction of travel-of the fabric and the remainder with lines running in other directions, which may be transverse as shown at 9. Again, some parts of the heated surface, e.g. those containing the lines 9, may be left plain. Yet again, some or all of the lines within the circular portions of FIG. 3 may be curved or wavy, as shown at 10 in FIGURE 4. The different glazing effects, together with the different forms of light reflection so produced, give the patterned effect on the fabric.

The degree of both shrinkage and reduction in glazing will vary according to the depth and shape of the lines, the angle which they make to the axis of the roller, and the number of lines per inch. Variation in the degree of shrinkage may produce a slightly undulating effect on the fabric.

A typical spacing of the shreiner lines is lines to the inch, measured parallel to the axis of the roller. By varying the spacing, a watered effect may be produced.

If the glazing is only reduced but not eliminated by the use of the schreiner lines, it may be reduced further by subjecting the fabric to the action of steam after it leaves the shrinking apparatus. In the apparatus shown in FIGURE 1 steaming should be effected before the fabric reaches the Palmer dryer 6. Such steaming also swells the fabric and improves the fullness of the handle.

We claim:

1. In an apparatus for compressively shrinking a fabric in the direction of its path of travel, said apparatus including a metal surface and a contractible surface between which the fabric is heated by the metal surface and compressively shrunk, the improvement whereby the glaze normally appearing on the face of the fabric which has been in contact with the heated metal surface is substantially reduced comprising having said metal surface engraved with schreiner lines extending in the direction of the travel of the fabric.

2. In an apparatus for compressively shrinking a fabric, said apparatus including a belt having a contractible surface and a heated metal pressure roller arranged so that the fabric is compressed in the direction of its path of travel between the heated metal roller and said surface, the improvement whereby the glaze normally appearing on the face of the fabric which has been in contact With the heated metal roller is prevented from forming comprising having the surface of said metal roller engraved with parallel schreiner lines extending about the periphery of the roller in a direction perpendicular to the axis of said roller.

37 In an apparatus for compressively shrinking a fabric, said apparatus including a belt having a contractible surface and a heated metal pressure roller arranged so that the fabric is compressed in the direction of its path of travel between the heated metal roller and said surface, the improvement whereby the glaze normally appearing on the face of the fabric which has been in contact with the heated metal roller is prevented from forming on a predetermined area of said fabric comprising having that portion of thesurface of said metal roller in contact with said predetermined area of said fabric engraved with schreiner lines. eXtendingin the direction of travel of the fabric.

4. In a process for compressively shrinking a fabric by passing said fabric between and in contactwith a heated metal surface and a contractible surface, the improvement whereby the glaze normally formed on the face of the fabric which has been in contact with the heated metal surface is subtantially reduced, comp-rising subjecting said face of said fabric at the point of contact between said metal surface and said contractible surface to a plurality of spaced, continuous, compressive forces normal to the direction of travel of said fabric, the spac ing between said forces being equivalent to the spacing of schreiner lines commonly used in calendering machines.

5. In a process for compressively shrinking a fabric by 4 I passing said fabric between and in contact with a heated metal surface and a contractible surface, the improvement whereby the glaze normally appearing on the face of the fabric which has been in contact With the heated metal surface is eliminated in predetermined areas of the face of said fabric, comprising subjecting said predetermined areas of the face of 'said fabric at the point of contact between said metal surface and said contractible surface to a plurality of spaced, continuous, compressive forces normal to the direction of travel of said fabric, the spacing between said forces being equivalent to the spacing of schreiner lines commonly used in calendering machines, the face of said fabric in contact with said plurality of compressive forces being unglazed, the remainder of the face of said fabric being glazed.

References Cited in the file of this patent UNITED STATES PATENTS 

